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Modern Gas tank venting system for a Gen 3 Hemi - anyone know how to do it? / Worth it?

Aron

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Hey All,
I'm putting in my new Fuel Tanks Inc. fuel tank into my '68 Charger. I'm running a 6.1 Liter built 3rd Gen Hemi. I'm going with the Holly EFI system. I've got the diagram and parts to run the sending line, return line, with fuel filter and regulator. That part I think I'm good on (thanks to folks on this site).

What I'm researching now is how to run the vent line(s). I've seen some folks (on this site) run the two vent lines to a Y connector, then up through the trunk ending in a check / roll over valve, some mount that in the trunk. One guy put a brake charcoal filter before the check valve.

My concern is gasoline smell, since I shelled out the money for the PTFE lines, I'm looking to eliminate any chance of smelling gas in the garage.
I've seen online that modern fuel systems run the tank vent into a charcoal canister that has a purge (on the bottom?), which then connects to a solenoid with a sensor controlled by the ECM, and that connects to the intake manifold. When the engine warms up, the sensor kicks over (on?) the solenoid. Then the fuel vapor is evacuated from the charcoal cannister and run into the intake manifold, where the fuel vapor is burned up.

Anyone do this? Have any thoughts? I'd love insight on how to do this from the ground up (assume I know nothing) - spending an awful lot of time and money on this car (I'm now 43, I've had it since I was 18, started the tear down and rebuild 11 years ago) -- might as well do it all the way.

Thanks all, as always, I appreciate the help!
-Aron
 
Myself I would just use the factory venting. Do not over think it.
 
I used the factory 68 venting in my 68 Charger. I have a 6.1 with the in tank pump and factory 6.1 injection. No fuel smell in my shop unless I spill some.
 
Still in the planning stage for later when I get to that area but I'm looking at adding a charcoal canister, along the line of what the cars came with early 70's on, to capture the fumes. The California swill doesn't help as the boiling point of the fuel, last time I saw, was 150* due to the CARB requirements plus the alcohol content. Also I'm going to up the vent line diameter to cut down on any restrictions. Some have used a tube with spirals bent in it like a still but that doesn't work well for venting when the vapor condenses back to a liquid and basically plugs the line up cutting off the venting. There have been numerous threads posted awhile back on vapor lock problems and how people got around it. Might be worth digging into the archives to get some ideas. On your thoughts of using late model emission tech for the vapor control, thats another possibility too. You'll need to have a sealed system with no vented cap. Some time back I started to research something like that for me which I'll need to continue for my car. On Chevy's E-Rod conversions, they have some sort of package to add this stuff onto earlier vehicles so its current technology fuel vapor and emission control compliant.
 
Thank you all so much for the help, this is really good stuff - because I am an *** and didn't pay attention when I was taking the car apart, what is the factor venting set up?
Thanks again.
 
Thank you all so much for the help, this is really good stuff - because I am an *** and didn't pay attention when I was taking the car apart, what is the factor venting set up?
Thanks again.
There is a line that runs off the upper end of the fill tube that runs down into the frame. Simple and works well. I have zero fumes even with a full tank.
 
Here is a pic of the stock Charger filler tube showing the vent tube pnora mentioned. It goes down through the trunk floor and is inserted into the frame rail. It is the only vent and works well with my 6.1 application. Never had any pressure build up, vacuum issues or odors. ( pic from another thread on this site dealing with fuel venting)

1169877-220c2020dbd25f3ba080ce79aed0c42c.jpg
 
I’ve been over-thinking my vent setup for a 6.2 hellcat motor and stealth fuel tank being installed in a 69 Charger . The new fuel line is 3/8” and l’m thinking the stock vent is fine for fuel expansion but I need something bigger to allow air into the tank when operating at high hp. I think the line needs a 1-way check and filter. The line needs to terminate at the stock vent elevation or higher. I’m worried about vapor inside the car though so I’ll be interested in what you decide. I’m gonna ask the Aeromotive boys about it soon as well.
 
The Stealth tank instructions for a hellcat swapped charger say:

Factory ventilation will be retained as per OEM spec.

So the stock vent should be fine on your car.
 
Having no trouble with the stock vent with EFI and peak fuel flow of 492 lb/hr
 
I run a II Much performance remote fuel vent in the trunk that exits out underneath the car. I have it mounted up on the trunk hinges (I have aftermarket strut hinges so it has a bit more room) so it is almost level with the gas cap. Almost no smell of gas in the garage.

Hooking it up was simple, from the tank & pump the 2 lines go into a Y fitting, then into a bulkhead in the floor, then a hose up to the vent, and another line goes back to a second bulkhead fitting in the floor into a filter. I can take some pictures of it if needed.

II MUCH VSR Vent System for Fuel, Differential, and Transmission P/N 200024

Looks like they updated the design from what I have but should be the same concept.
 
For what the poster is doing he only needs to adhere to the KISS theory. No need to over complicate and overspend when the stock vent will do everything he needs.
 
Old cars with modern engines and electronics shouldn't have to deal with gas smells. What I do is run the tank vent lines to a charcoal canister with a vent valve (can be integral or separate). I use a purge solenoid connected to the Holley ECM to activate the valve for a set time on startup, under no load conditions. It's a simple and easy solution to never have to deal with the tank smell again.
 
For what the poster is doing he only needs to adhere to the KISS theory. No need to over complicate and overspend when the stock vent will do everything he needs.
I have a 5.7 EFI and '69 OE venting. No smells at all.
 
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